imo, they do purify the air.

This post has been edited by cedyy: Sep 17 2018, 12:09 PM

effective in removing dust and odour. i had stubborn durian odour in car for a few days. left the air purifier in the car overnight and the smell had reduced significantly in one night. repeated for another day and it was almost gone.

also, i have one in the wardrobe to help control fungus which used to plague my clothes especially those not worn for sometime.

All purifiers are supposed to work in enclosed condition. Theres effective area stated for different models

Sharp FPF40LW with hepa filter and ionizer

low hum sound becoming apparent now as it ages..lol. it was quiet when new. i no longer put it in bedroom, i put it in my study room instead. the higher end models should not have this problem. same with low end panasonic fpx-j30a which was okay when new but then started to emit humming sound after a year. now i put it in my wardrobe to prevent mould. but the panasonic fpxm55 which is in my bedroom is very silent even after a year